PTGER2 and esophageal ulcer: A repurposing signal between misoprostol and an SNP on the type 2 prostaglandin E receptor (PTGER2) was detected by a workflow similar to that in this article; the associated PTGER2 PheWAS hits were significantly enriched for gastritis and duodenitis, and esophageal ulcer.42 More information on the design of NCT03617172 is available in Appendix Figure A3.